Swap Vessel is a functionality that allows you to change the vessel of the voyage, regardless the status of the voyage. There are two ways to change the vessel; through the Vessel field under Voyage Overview, or through the secondary action 'Swap Vessel'.
For voyages with status Estimate or Unallocated, you can only swap the vessel of the voyage through the Vessel field found under Voyage Overview section:
This works as a normal dropdown menu, that views all available vessels for you to click and swap to.
For voyages with status Allocated or above, you can only swap the vessel of the voyage through the secondary action called 'Swap Vessel':
Followed by clicking the action, this modal will pop up:
In this modal, a vessel must be selected to be able to swap. By default, the vessel you are currently on is selected. Meaning, you are always able to actually click on the Swap button (for now). After the swap, you are able to see the new vessel either as the above mentioned Vessel field under Voyage Overview, or at the top of the Voyage drawer, left-most (clickable) chip:
